// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_RENDERER_HOST_PEPPER_PEPPER_NETWORK_PROXY_HOST_H_
#define CONTENT_BROWSER_RENDERER_HOST_PEPPER_PEPPER_NETWORK_PROXY_HOST_H_

#include <stdint.h>

#include <queue>
#include <string>

#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "content/common/content_export.h"
#include "net/proxy/proxy_service.h"
#include "ppapi/host/host_message_context.h"
#include "ppapi/host/resource_host.h"

namespace net {
class ProxyInfo;
class URLRequestContextGetter;
}

namespace ppapi {
namespace host {
    struct ReplyMessageContext;
}
}

namespace content {

class BrowserPpapiHostImpl;

// The host for PPB_NetworkProxy. This class lives on the IO thread.
class CONTENT_EXPORT PepperNetworkProxyHost : public ppapi::host::ResourceHost {
public:
    PepperNetworkProxyHost(BrowserPpapiHostImpl* host,
        PP_Instance instance,
        PP_Resource resource);

    ~PepperNetworkProxyHost() override;

private:
    // We retrieve the appropriate URLRequestContextGetter and whether this API
    // is allowed for the instance on the UI thread and pass those to
    // DidGetUIThreadData, which sets allowed_ and proxy_service_.
    struct UIThreadData {
        UIThreadData();
        UIThreadData(const UIThreadData& other);
        ~UIThreadData();
        bool is_allowed;
        scoped_refptr<net::URLRequestContextGetter> context_getter;
    };
    static UIThreadData GetUIThreadDataOnUIThread(int render_process_id,
        int render_frame_id,
        bool is_external_plugin);
    void DidGetUIThreadData(const UIThreadData&);

    // ResourceHost implementation.
    int32_t OnResourceMessageReceived(
        const IPC::Message& msg,
        ppapi::host::HostMessageContext* context) override;

    int32_t OnMsgGetProxyForURL(ppapi::host::HostMessageContext* context,
        const std::string& url);

    // If we have a valid proxy_service_, send all messages in unsent_requests_.
    void TryToSendUnsentRequests();

    void OnResolveProxyCompleted(ppapi::host::ReplyMessageContext context,
        net::ProxyInfo* proxy_info,
        int result);
    void SendFailureReply(int32_t error,
        ppapi::host::ReplyMessageContext context);

    // The following two members are invalid until we get some information from
    // the UI thread. However, these are only ever set or accessed on the IO
    // thread.
    net::ProxyService* proxy_service_;
    bool is_allowed_;

    // True initially, but set to false once the values for proxy_service_ and
    // is_allowed_ have been set.
    bool waiting_for_ui_thread_data_;

    // We have to get the URLRequestContextGetter from the UI thread before we
    // can retrieve proxy_service_. If we receive any calls for GetProxyForURL
    // before proxy_service_ is available, we save them in unsent_requests_.
    struct UnsentRequest {
        GURL url;
        ppapi::host::ReplyMessageContext reply_context;
    };
    std::queue<UnsentRequest> unsent_requests_;

    // Requests awaiting a response from ProxyService. We need to store these so
    // that we can cancel them if we get destroyed.
    std::queue<net::ProxyService::PacRequest*> pending_requests_;

    base::WeakPtrFactory<PepperNetworkProxyHost> weak_factory_;

    DISALLOW_COPY_AND_ASSIGN(PepperNetworkProxyHost);
};

} // namespace content

#endif // CONTENT_BROWSER_RENDERER_HOST_PEPPER_PEPPER_NETWORK_PROXY_HOST_H_
